In this article, fracture behavior of multi-layered composite processed via accumulative roll bonding (ARB) method has been investigated. At first, Al1050/Cu/MgAZ31B multi-layered composite has been prepared by ARB through seven passes. The microstructure and mechanical properties have been evaluated using uniaxial tensile test, microhardness test and optical microscope, respectively. Then, the plane stress fracture toughness of Al1050/Cu/MgAZ31B have been studied via R-curves. Also, tensile fracture surfaces have been demonstrated by scanning electron microscope (SEM). The results of microstructure investigations have indicated that plastic instability occurred for both pure Cu and Mg AZ31B reinforcing at the primary sandwich and uniform distribution has been processed. By increasing the applied strain, the values of microhardness for the three layers Al1050, pure Cu, and Mg AZ31B as well as ultimate tensile strength (UTS) have been significantly increased, continually, and UTS has reached to the maximum value of 355.5 MPa. SEM images of the tensile rupture surfaces in the different ARB passes have demonstrated that with increasing the applied strain, the fracture mode converted to shear ductile at the last ARB pass. Results of fracture test have shown that by increasing the applied strain, the value of fracture toughness have been raised, continually and at the third pass reached to the maximum value of 40.4 MPam^1/2. Also, the trends of fracture toughness for Al1050/Cu/MgAZ31B were in great matching with the conclusions of the fracture behavior investigation of Al1050 produced by ARB.

本文研究了通过累积辊压粘结（ARB）方法处理的多层复合材料的断裂行为。首先，ARB通过7道次制备了Al1050 / Cu / MgAZ31B多层复合材料。分别使用单轴拉伸试验，显微硬度试验和光学显微镜评价了显微组织和力学性能。然后，通过R曲线研究了Al1050 / Cu / MgAZ31B的平面应力断裂韧性。而且，拉伸断裂表面已经通过扫描电子显微镜（SEM）证实。微观结构研究的结果表明，纯Cu和Mg AZ31B增强材料在一次夹层中均发生了塑性不稳定性，并且已经处理了均匀分布。通过增加施加的应变，三层Al1050，纯Cu和Mg AZ31B的显微硬度值以及极限抗拉强度（UTS）不断提高，并且UTS达到了355.5 MPa的最大值。SEM图像在不同的ARB道次中均显示出，随着施加应变的增加，断裂模式在最后一次ARB道次时转变为剪切韧性。断裂试验结果表明，通过增加外加应变，断裂韧性值不断提高，第三遍达到最大值40.4 MPam。SEM图像在不同的ARB道次中均显示出，随着施加应变的增加，断裂模式在最后一次ARB道次时转变为剪切韧性。断裂试验结果表明，通过增加外加应变，断裂韧性值不断提高，第三遍达到最大值40.4 MPam。SEM图像在不同的ARB道次中均显示出，随着施加应变的增加，断裂模式在最后一次ARB道次时转变为剪切韧性。断裂试验结果表明，通过增加外加应变，断裂韧性值不断提高，第三遍达到最大值40.4 MPam。^1/2。另外，Al1050 / Cu / MgAZ31B的断裂韧性趋势与ARB生产的Al1050断裂行为研究的结论非常吻合。